Barry, 77, a former mayor of Washington, acknowledged in financial disclosure statements he received a total of $6,800 from two local contractors.
Council members, who are tasked with approving contracts valued at over $1 million, are prohibited from accepting gifts worth more than $20 from businesses with city contracts, the Washington Times reported Friday.
The Board of Ethics and Government Accountability imposed a $13,600 penalty on Barry Thursday, the newspaper said.
A U.S. Attorney's Office spokesman declined to say whether federal prosecutors would take any action as a result of the investigation.
Barry, a four-term mayor who was jailed while in office in the 1990s on a misdemeanor cocaine possession charge, was censured in 2010 after a report noted he violated conflict-of-interest rules in handing a contract to a former girlfriend.